Evolution of Surface Plasmon Supermodes in Metal-Clad Microwire and Its Potential for Biosensing

A finite-element method based on the vector H-field formulation in conjunction with perturbation techniques is used to study metal-clad microwire waveguides for bio-sensing applications. Sensors are designed to detect DNA hybridization through the change of the effective index and attenuation constant of the waveguide structure. The key parameters, such as effective index, loss coefficient, and spot sizes, are presented and potential sensor applications are discussed.